Which of the following statements of correct for the spontaneous adsoption of a gas?

Options

A. `DeltaS` is negative and therefore, `DeltaH` should be highly positive.
B. `DeltaS` is negative and therefore, `DeltaH` should be highly negative.
C. `DeltaS` is positive and therefore, `DeltaH` should be highly negative.
D. `DeltaS` is positive and therefore, `DeltaH` should be highly positive.

Answer

B

Explanation

For adsorpition `DeltaSlt 0` and for a spontaneous change `DeltaG=-ve`
Hence `DeltaH` should be highly negative which is clear from the equation
`DeltaG=DeltaH-TDeltaS`
`=-DeltaH-T(DeltaS)=-DeltaH+TDeltaS`
So if `DeltaH` is highly negative, `DeltaG` will also be `-ve` .